Electric stop motion for knitting machines



May 20, 1941. a. WACHSMAN 2,242,875

ELECTRIC STOP MOTION FOR KNITTING MACHINES Filed April 6, 1940 Imq -L I I I; .1

11 7X 2 f9 9 12 [/3 i9 BOBB/N JUICE}- INVENTOR @Wizw Patented May 26, 1941 UNiTE STATES PATENT @FFKZE ELEL'TRZC ll IOTION FOR KNITTING BIACHINES York Application April 6. 1949, Serial No. 322,250

1 Claim.

This invention relates to electric stop motions for knitting machines. Such devices, which are controlled by the travelling yarn, may be classifled into end detectors and knot detectors. The end detectors are arranged to operate to close an electric circuit when the yarn breaks or runs out. The knot detectors operate to close the circuit when a knot or other obstruction occurs in the yarn.

The object of this invention is to provide a combined end detector and knot detector into a single device which may be used in place of the two separate devices or which may be used indiscriminately as an end detector or as a knot detector. In the ace-on panying drawing illustrating the invention Fig. 1 is a side view of the device.

Fig. 2 is a face View looking from Fig. 1.

Fig. 3 is a plan View.

Fig. 4 is a detail view of mo be used in the device.

Those who are familiar with the art of knitting machines know that stop motions are mounted in a suitable position in the machine in the path of the travelling yarn. They are also entirely familiar with the operations and functions of such devices so no extended description as to these features are necessary in this specification. Now referring to the drawing the stop motion device is mounted upon a bar 5 which represents any suitable member of a knitting machine. The bar carries a screw or bolt 6 with a knurled or other nut 2|. Upon the bolt is supported a rotatable disk I which has porcelain eyelets 8, 8 of graduated sizes. Upon the bolt 6 is also placed a bracket 9 which carries a contact box iii. The upper end of the bracket is provided with a porcelain eyelet II of the same size as the largest eyelet 8. A detector lover I: is pivoted at G3 in the box ill. The lever has a yarn engaging eye or loop l4 adapted to enclose and rest against the yarn l5 above the eyelet H. Inside the box the lever l2 has a contact heel it. When the yarn breaks or runs out or when a slack occurs in the yarn the lever l2 falls forward by gravity and its contact heel then contacts a spring terminal I! inside the box to close an electric circuit, said inside terminal being connected at It to an outside terminal l9 through insulation 20. Spacing washers 28 and 29 are provided to permit free rotation of the disk I.

In operation the device is mounted upon the bar 5 and nut 2i screwed down sufficiently so that the device is held on the bar. Then the disk I is rotated so as to bring a particular eyelet 8 into alinement with the eyelet ll so that the yarn l5 can be passed straight upwards through such eyelets as shown, the nut 2! being loosened suflicient- 1y to permit such rotation. Then the nut 2| is the leit in member to tigl'itened to hold the disk in such selected tion. The eyelet 3 selected for alinement is chosen with relation to the yarn. If the yarn is very fine, a very small eyelet 8 is brought into operating position. For thicker yarns maybe for yarns being fi-ossier a correspondingly larger eyelet 8 is selected. For each yarn the selected eyelet 8 is such that when a knot occurs upon the yarn, it cannot pass upwards through the selected eyelet.

The operation is therefore this. When the yarn breaks or runs out the detector will fall forward and close the circuit. If a knot occurs on the yarn it cannot pass upwards through the selected eyelet 8 in the disk I. The yarn therefore cannot travel through the device or machine. The yarn breaks and the detector lever is again operated.

In place of the disk "I an arm 25 such as shown in Fig. 4 may be used. The arm has a hole 26 which fits over the bolt 6. It also carries two different sized procelain eyelets 21 and '23. By substituting the arm 25 for the disk l the device becomes somewhat simpler and more inexpensive.

t will be understood that in this case the arm is moved slightly on the bolt 6 in order to bring the selected eyelets 2? or 28 into a linement with the said eyelet ll. Several arms having combined a complete series of graduated eyelets may be provided for a single kniting machine for ready selection of the proper eyelet.

The device is inexpensive, easy to install and operate and serves as a com ined end detector and knot detector depending upon the kind of yarn used and adjustment of the device.

I claim:

In a combined end detector and knot detector for knitting machines, a unitary article of manufacture comprising a supporting bracket including a horizontal arm and an upright arm, a fixed yarn guiding eyelet in the upright arm, a disk rotatably supported on the horizontal arm below the same a distance below said fixed eyelet, a plurality of yarn guiding eyelets of different sizes mounted in said disk, said disk being adapted to selectively move any one of the eyelets therein into yarn guiding alinement with said fixed eyelet, a bolt in said bracket for rotatably supporting the said disk thereon and for mounting said bracket on a knitting machine, a nut on said bolt for securing said disk after the eyelets therein have been alined as aforesaid and for securing the bolt to the knitting machine, a contact box on said horizontal bracket arm and a gravity actuated lever pivoted on said box to close an electric circuit therein, said lever extending forwardly of said bracket into engagement with a yarn passing through the alined eyelets.

BEN WACHSMAN. 

